Fumigant and process of fumigating



v I to be very cumbersome and hazardous.

Patented Dec. 31, 1946 UNITEDI'I'STATE FUMIGANT AND PROCESS OF FU MIGATING Willis Canard Fernelius, Dayton, Ohio, and Frank I Leslie Campbell, Ro'ckville, Md.

No Drawing. Application July 21, 1944,-

- Serial No. 546,060

Claims. (Cl. 167- 39) This invention, which is a continuation-in parli of .the invention of our application Serial No. 403,873, filed July 24, 1941, and published August 7, 1945, as United States Patent No. 2,381,257, re-

lates to the preparation of addition products of sulfur dioxide and dioxan (diethylene oxide) and to the use of the compounds in a process for killing insects.

In accordance with this invention, sulfur dioxide and diethylene oxide are reacted at relatively low-temperatures to form new addition tically necessary to engage professional fumigators. Also, in many instances where, for example, the space to be fumigated was small, theuse of compressed sulfur dioxide was impractical. The

use of sulfur candles has always left much to be desired. In addition to the dangers attendant upon the burning of sulfur, the method at best was haphazard and it gave no assurance that suillcient sulfur dioxide would be generated for comcompounds having the formula C(CzHOzO-SOa and 0(C2H4) 20-2802. It is believed that the oxygen atoms of the dioxan serve individually as donors of pairs of electrons to the sulfur atom of sulfur dioxide. linkage is formed between said oxygen and sulfur atoms. When dioxan and sulfur, dioxide are reacted in equimolecular proportions, a compound having theformula 0(C2H4) 20:50: is formed, whereas when two mols of sulfur dioxide are reacted per mol of dioxan, the product has the formula OaS-O(C2H4) 20-802. Intermediate amounts of sulfur dioxide result in a mixture of the two products.

The products, which are liquid at normal room temperatures, have a high vapor pressure and volatilize very readily at atmospheric pressure. Because of this tendency to vaporize rapidly at room temperatures, the compounds can be used;

compounds is fast and thorough due to the insecticidal properties of both the dioxan and the sulfur dioxide which are liberated.

While it is well known to fumigate with sulfur dioxide, such fumigating processes have proven Heretofore, it was necessary to use compressed sulfur dioxide or to burn either sulfur candles or carbon disulflde'absorbed on diatomaceous earth. Unskilled operators could not use compressed gas without endangering themselves, and it was prac- In this way, a relatively weak I plete and thorough fumigation. burning of carbon disulflde was both unsatisfactory and particularly hazardous.

When the products of this invention are used as fumigants, there is no risk of danger to operators. Furthermore, thorough fumigation is assured because the compounds are of known composition and volatilize completelyat room temperature; and, therefore, theamou'nt required for fumigating any given enclosure can be calculated or estimated easily. I This also-makes for 1 economy, as only the required amount need be used. In the fumigating of insect-infested enclosures, it is necessary only to open a container of the addition products and to vaporize a suflicient amount of compound to kill all insects therein. The container may be, for example, a can with a lid or portion which may be easily removed or puncburning sulfur is avoided. Alternatively, the compound may be sprayed into enclosures which require fumigation. This can be done very conveniently by means ofcontainers equipped with a thumb-operated valve, such as the so-called siphon used in dispensingcharged water orthe device used to apply whipped cream by releasing nitrous oxide under pressure. A particularly satisfactory method of employing the material of this invention is to saturate powders, pellets, or balls of clay, diatomaceous earth, talc, and the like, with the compound. These may be kept in sealed containers and used as needed. Extenders. I I

solid carriers, or fillers thus saturated are espe- Similarly, the

cially suited for use in small enclosures such as drawers, boxes, closets, et cetera.

Diluents or liquid carriers which are miscible with the addition compound may be used in conjunction therewith. Their presence often facili-- tates the use of the addition compound. Suitable liquid carriers include miscible hydrocarbon solvents and halogenatedhydrocarbon solvents.

The addition products of dioxan and sulfur are prepared by passing the latter into liquid dioxan. It is advisable to maintain the liquid dioxan at lower than room temperatures. Alternatively, the two materials may be reacted in an autoclave under pressure at higher temperatures. Low temperatures are required for the prepara- 4 ratio of one mol of the former to two mols of the latter, said product having the formula prises exposing insects to the vapors of an addition of the compound in whichtwo' mols of 1 sulfur dioxide are reacted with one mol of dioxan.

Preferably, between one and two mols of sulfur dioxide to dioxan are reacted, although a considerable excess of the diethylene oxide may be present if desired. x

The following example illustrates a preferred method of preparing the addition products of diethylene oxide and sulfur dioxide.

Into a tared flask containing 600. grams (5" tion product of dioxan and sulfur dioxide.

'5. A process for-fumigatingan insect-infested jenclosure which comprises vaporizing at atmospheric pressure within said enclosure the addition products of dioxan and sulfur dioxide in an amount suflicient to kill all insects within said enclosure.

mols) of dioxan was passed at room temperature 320 grams (5 mo1s) of sulfur dioxide. The flask was then cooled by immersion in a salt-ice bath, and addition of sulfur dioxide was continued until a total of 640 grams (10 mols) of sulfur dioxide had reacted.

The product of the reaction at room temperature had the formula O(C2H4)zO-SO2, and the final product had the formula ms-owlnmo-so:

Bothcomp'ounds were liquids at room temperature and had high vapor pressures. I

We claim: i

As a new composition of matter, the addiy' tion product of 'dioxan and sulfurdioxide in the 6. The methodof killing insects which comprises exposinginsects to the vapors of an addition product of dioxan, and sulfur dioxide, said product having the formula O(CzH4)2O.-SO2.

'7. The method of. killing insects which comprises exposing 'insects to the vapors of an addition product of dioxan and sulfur dioxide, saidproduct having the formula O2S-O(CzH4) 2O-SOz. 8. A fumigating and insecticidal composition comprising the compound 02S O (C2114) 2O SO:

3 and a carrier therefor. I

9. Afumigating and insecticidal composition comprising the compound O2S-O(C2H4')2O'SO2 and a solid carrier therefor. 10. A fumigating and insecticidal composition comprising the. compound O2S'O(C2H4) 20-802 and aiiquid diluent therefor."

Y WILLIS CONARDFERNELIUSs FRANK LESLIE CAMPBELL. 

